The present invention relates to a solid state image pickup device, signal processing method and camera therefor and more particularly relates to a solid state image pickup device, signal processing method and camera therefor employing a wide dynamic range Charge Coupled Device (hereinafter referred to as xe2x80x9cCCDxe2x80x9d) solid state image pickup element.
With usual CCD solid state image pickup elements, since the signal output becomes constant after a signal charge obtained by performing photoelectric conversions at each pixel overflows the pixel, no signal output can be obtained for amounts of further incident light and dynamic range with respect to incident light is therefore narrow. In response to this, there is well known a solid state image pickup element that achieves a broader dynamic range by obtaining a signal charge of a long accumulation time and a signal charge of a short accumulation time for the same pixel and sequentially outputting a signal based on the signal charge accumulated over a long period of time and an addition signal obtained by adding the signal charges accumulated over a long period of time and a short period of time, with the addition signal being utilized when there are large amounts of incident light.
With the aforementioned wide dynamic range CCD solid state image pickup element, a single sampler is provided at the following stage. One of either a long accumulation time signal or a signal that is the sum of the long accumulation time signal and the short accumulation time signal are then sampled by this sampler. This means that only either the long accumulation time signal or the signal that is the sum of the long accumulation time signal and the short accumulation time signal can be outputted and that these signals cannot be outputted at the same time.
As the present invention sets out to resolve the aforementioned problems, it is the object of the present invention to provide a solid state image pickup device, signal processing method and camera thereof where required signals can be arbitrarily extracted without having to change the configuration or operation of the solid state image pickup element at all when using the solid state image pickup element to sequentially output from the same output terminal a plurality of signals of different sized for the same pixel.
In order to resolve the aforementioned problems, the solid state image pickup device of the present invention comprises a solid state image pickup element and a signal processor. The solid state image pickup element is for sequentially outputting a plurality of signals of different sizes for the pixel from the output terminal. The signal processor is for sampling and outputting the plurality of signals sequentially outputted from the solid state image pickup element.
Further, a signal processing method for a solid state image pickup device employing a solid state image pickup element for sequentially outputting a plurality of signals of different sizes for the pixel from the output terminal comprises a step of sampling and outputting the plurality of signals sequentially outputted from the solid state image pickup element.
Moreover, camera comprises a solid state image pickup element, an optical system and a signal processor. The solid state image pickup element is for sequentially outputting from the output terminal a plurality of signals of different sizes for a pixel. The optical system is for guiding light from an object to a light receiving surface of the solid state image pickup element. The signal processor is for sampling and outputting the plurality of signals sequentially outputted from the solid state image pickup element.